As a prior art relating to HAT (Humid Air Turbin) cycle, in U.S. Pat. No. 5,507,141, Japanese Patent Publication No. Hei 1-31012, Japanese Patent Publication No. Hei 1-195053, Japanese Patent Laid-open No. Hei 9-264158, and Japanese Patent Laid-open No. Hei 10-103079 is described a gas turbine cycle for carrying out heat recovery of exhaust of a turbine or heat recovery of exhaust of a turbine and intermediate cooling of a compressor by a liquid phase mixture of compressed air/water/steam obtained by pouring liquid phase water into a part or the whole of compressed air obtained by compressing by the compressor air used as self-sustained combustion gas, working medium gas or the like of gas mainly comprising air.
It has been contemplated that the above gas turbine cycle can achieve the output and high efficiency equal to of more than those of the combined cycle merely by a gas turbine without requiring a steam turbine, but a problem of consuming a large the quantity of water has been also pointed out.
So, in “FT4000 HAT WITH NATURAL GAS FUEL” on pages 239 to 245 of “IGTI-Vol. 7, ASME COGEN-TURBO 1992”, Japanese Patent Laid-open No. Hei 10-30811, and Japanese Patent Laid-open No. Hei 10-110628, a system for recovering moisture from exhaust gases of the gas turbine for recycle or recirculation is contemplated. The exhaust gas from which moisture is recovered is at a temperature of, for example, approximately 40° C. which is lower than a condensation temperature (100° C.), but since the exhaust gas cannot be released into atmosphere at that temperature in terms of environment, exhaust gas from which moisture has been recovered is heat exchanged with exhaust gas prior to recovery of moisture to reheat it.
In the above-described prior arts, the exhaust gas prior to recovery of moisture is used as a reheating medium for the exhaust gas from which moisture has been recovered to carry out heat exchanging between gas and gas. As a result, heat exchanging equipment becomes large-scaled and pressure loss of exhaust gas increases. Since pressure of exhaust gas at an inlet of a chimney is determined in a relation with atmospheric pressure, when pressure loss of exhaust gas before reaching the chimney increases, pressure of exhaust gas at an outlet of the gas turbine need be made high. That is, a pressure difference in a working medium between the inlet and outlet of the gas turbine is so small that output of the gas turbine is small. However, such a point as just mentioned has not been studied in the above-described prior arts.
Further, in the above-described prior arts, a humidifying tower has been used to humidify compressed air supplied to the gas turbine. The detailed construction of the humidifying tower is described in, for example, U.S. Pat. No. 2,186,706, or the like.
In the above conventional humidifying tower, compressed air and water are brought into contact in an opposite flow and directly. That is, in the humidifying tower, waterdrops sprayed or dropped are brought into direct contact through a porous medium (which promotes contact between compressed air and water) with compressed air flowing in an upper direction, and moisture is added to the compressed air.
Therefore, since the conventional humidifying tower is operated in the opposite flow and through the porous medium, pressure loss of compressed air is extremely large. When the pressure loss of compressed air is large, pressure of the working medium of the gas turbine is small, and the output of the gas turbine is small. However, nothing on such a point as described has been studied in the above-described prior arts.
It is a first object of the present invention to provide gas turbine electric power generation equipment which reduces pressure loss of burned exhaust gas of a gas turbine to improve output or efficiency of electric power generation.
It is a second object of the present invention to provide gas turbine electric power generation equipment which reduces pressure loss of a working medium of a gas turbine to improve output or efficiency of electric power generation.
It is a third object of the present invention to provide an air humidifier which, while reducing pressure loss of a working medium of a gas turbine, adds moisture to the working medium for humidification.